1. Field of the Invention
The present invention relates to novel compounds which are effective for prevention and treatment of various diseases associated with abnormal angiogenesis, and to medical compositions such as angiogenesis inhibitors and antitumor agents comprising the novel compounds.
2. Related Background of the Invention
Angiogenesis is an essential biological phenomenon for fetal vascular formation and morphological and functional development of organs. New blood vessels are assembled through several processes including endothelial cell migration, proliferation and tube formation, and the participation of mast cells, lymphocytes, interstitial cells and the like has been shown to be important in this process (J. Folkman and Y. Shing, J. Biol. Chem., 267, 10931, 1992). In adult individuals, physiological angiogenesis occurs during the female estrous cycle, but pathological increase in angiogenesis in adult individuals is known to be connected with onset or progression of various diseases. Specific diseases associated with abnormal angiogenesis include cancer, rheumatoid arthritis, atherosclerosis, diabetic retinopathy, angioma, psoriasis, and the like (J. Folkman, N. Engl. J. Med., 333, 1757, 1995). In particular, the literature has indicated angiogenesis dependency for solid tumor growth, and angiogenesis inhibitors are therefore promising as new therapeutic agents for intractable solid tumors (J. Folkman, J. Natl. Cancer Inst., 82, 4, 1990).
The prior art includes compounds based on a urea structure, described in WO99/00357 and WO00/43366. WO99/00357 mentions biphenylurea derivatives which have an inhibiting action on raf kinase and an antitumor effect, but their angiogenesis-inhibiting effect is not disclosed. WO00/43366 describes quinoline derivatives and quinazoline derivatives which exhibit a weak karyomorphism-altering effect on A375 human melanoma cells in vitro and an antiproliferative effect on endothelial cells stimulated by vascular epithelial growth factor (VEGF), and which thus have an antitumor effect, but their effect on angiogenic factors other than VEGF is not disclosed.